mpc85xx: HPE MSM460 add HPE MSM430 alias

mpc85xx: HPE MSM460 add HPE MSM430 alias

Define MSM430 as alternative name, to explicitly show the device is
supported using existing image (MSM460).

I can confirm that the guide from
https://github.com/blocktrron/msm460-flashing works perfectly fine with
the HP MSM430 as well.

In fact, the MSM430 running the original firmware operates as
a 2x3:2 access point, but after flashing it with OpenWRT, it functions
as a 3x3:3 access point — just like the MSM460 model.

It seems that the MSM430 is essentially the same hardware as the MSM460,
with limitations imposed by the original (HP) software.

Signed-off-by: Jan Taczanowski <jan.taczanowski@gmail.com>
Link: https://github.com/openwrt/openwrt/pull/19540
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>